Linux, Ubuntu 10.04.1 LTS
I have a (quite old) server (Dell PowerEdge 1650) with two CPUs. I have used it for over a year without any problems.
One week ago the server crashed, I was unable to find any errors in any logs, i rebooted and everything seemed to work well. Two hours later when i had upgraded the OS i noticed that I could only see one CPU.
$ cat /proc/cpuinfo | grep processor
processor : 0
I rebooted several times, and once, only once the system found two CPUs.
What do you think? Are we talking about broken software or hardware? I can't see anything wrong during boot, BIOS shows what i have "Two 1266 MHz Processors".
One theory is that one CPU is dead, but if that was the case shouldn't BIOS complain? The server was moved two weeks ago, maybe one CPU is not correctly connected to the socket?
I have no idea where to begin to debug this, any ideas?